MODULAR CAGE SYSTEM
Disclosed are devices for the fixation and support of vertebrae, particularly spinal implant devices formed from modular components of different materials.
This application is a continuation of U.S. patent application Ser. No. 16/688,791 entitled “MODULAR FOOTPRINT CAGE SYSTEM,” filed Nov. 19, 2019, which is a continuation-in-part of U.S. patent application Ser. No. 16/291,278 entitled “MODULAR PLATE AND CAGE ELEMENTS AND RELATED METHODS,” filed Mar. 4, 2019, which in turn is a continuation of U.S. patent application Ser. No. 15/244,868 entitled “MODULAR PLATE AND CAGE ELEMENTS AND RELATED METHODS,” filed Aug. 23, 2016, which claims priority to and benefit of U.S. Provisional Patent Application No. 62/270,141 entitled “MODULAR PLATE AND CAGE ELEMENTS AND RELATED METHODS,” filed Dec. 21, 2015. This application also claims priority to and benefit of U.S. Provisional Patent Application No. 62/769,450 entitled “MODULAR FOOTPRINT CAGE SYSTEM,” filed Nov. 19, 2018 via U.S. patent application Ser. No. 16/688,791. The disclosures of each of these references are incorporated by reference herein in their entireties.
FIELD OF THE INVENTIONThe present subject matter relates generally to devices for the fixation and support of vertebrae. In particular, the present subject matter relates to an implant device having adjustability.
BACKGROUND OF THE INVENTIONThe spinal column of vertebrates provides support to bear weight and protection to the delicate spinal cord and spinal nerves. The spinal column includes a series of vertebrae stacked on top of each other. There are typically seven cervical (neck), twelve thoracic (chest), and five lumbar (low back) segments. Each vertebra has a cylindrical shaped vertebral body in the anterior portion of the spine with an arch of bone to the posterior, which covers the neural structures. Between each vertebral body is an intervertebral disk, a cartilaginous cushion to help absorb impact and dampen compressive forces on the spine. To the posterior, the laminar arch covers the neural structures of the spinal cord and nerves for protection. At the junction of the arch and anterior vertebral body are articulations to allow movement of the spine.
Various types of problems can affect the structure and function of the spinal column. These can be based on degenerative conditions of the intervertebral disk or the articulating joints, traumatic disruption of the disk, bone or ligaments supporting the spine, tumor or infection. In addition, congenital or acquired deformities can cause abnormal angulation or slippage of the spine. Anterior slippage (spondylolisthesis) of one vertebral body on another can cause compression of the spinal cord or nerves. Patients who suffer from one of more of these conditions often experience extreme and debilitating pain and can sustain permanent neurological damage if the conditions are not treated appropriately.
Alternatively, or in addition, there are several types of spinal curvature disorders. Examples of such spinal curvature disorders include, but need not be limited to, lordosis, kyphosis and scoliosis.
One technique of treating spinal disorders, in particular the degenerative, traumatic and/or congenital issues, is via surgical arthrodesis of the spine. This can be accomplished by removing the intervertebral disk and replacing it with implant(s) and/or bone and immobilizing the spine to allow the eventual fusion or growth of the bone across the disk space to connect the adjoining vertebral bodies together. The stabilization of the vertebra to allow fusion is often assisted by the surgically implanted device(s) to hold the vertebral bodies in proper alignment and allow the bone to heal, much like placing a cast on a fractured bone. Such techniques have been effectively used to treat the above-described conditions and in most cases are effective at reducing the patient's pain and preventing neurological loss of function.
The spinal curvature disorders and/or contour issues present on the surfaces of the vertebrae may present additional challenges. As such, there is need for further improvement, and the present subject matter is such improvement.
BRIEF SUMMARY OF THE INVENTIONThe following presents a simplified summary of the subject matter in order to provide a basic understanding of some aspects of the subject matter. This summary is not an extensive overview of the subject matter. It is intended to neither identify key or critical elements of the subject matter nor delineate the scope of the subject matter. Its sole purpose is to present some concepts of the subject matter in a simplified form as a prelude to the more detailed description that is presented later.
In accordance with an aspect of the present subject matter, an implant device for the spine is provided. The implant device is for location between two adjacent vertebrae. The implant device includes: a first engagement surface configured to interface with a first of the two adjacent vertebrae; a second engagement member configured to interface with a second of the two adjacent vertebrae; and various modular components for independently adjusting a surface area or “footprint” of at least one of the first and/or second engagement surfaces.
In accordance with another aspect of the present subject matter, an implant device for the spine is provided. The implant device is for location between two adjacent vertebrae. The implant device includes: a first engagement member configured to interface with a lower surface of an upper vertebrae and an upper surface of an adjacent lower vertebrae; a second engagement member configured to interface with the lower surface of the upper vertebrae and the upper surface of the adjacent lower vertebrae; wherein at least a portion of the second engagement member is contained within at least a portion of the first engagement member.
In accordance with another aspect of the present subject matter, an implant device for the spine is provided. The implant device is for location between two adjacent vertebrae. The implant device includes: a first engagement member configured to interface with a lower surface of an upper vertebrae and an upper surface of an adjacent lower vertebrae, the first engagement member having an opening therein that extends from a lower implant surface to an upper implant surface; a second engagement member configured to interface with the lower surface of the upper vertebrae and the upper surface of the adjacent lower vertebra, the second engagement member sized to fit completely within the opening in the first engagement member.
In accordance with another aspect of the present subject matter, an implant device for the spine is provided. The implant device is for location between two adjacent vertebrae. The implant device includes: a first engagement member configured to interface with a lower surface of an upper vertebrae and an upper surface of an adjacent lower vertebrae, the first engagement member having an opening therein that extends from a lower implant surface to an upper implant surface; a second engagement member configured to interface with the lower surface of the upper vertebrae and the upper surface of the adjacent lower vertebra, the second engagement member nesting within and it contact with an inner surface of the first engagement member.
In accordance with another aspect of the present subject matter, a method for manufacturing an implant device as set for within any of the details described with the present application is provided.
In accordance with another aspect of the present subject matter, an implant device for the spine as set for within any of the details described with the present application is provided.
While embodiments and applications of the present subject matter have been shown and described, it would be apparent that other embodiments, applications and aspects are possible and are thus contemplated and are within the scope of this application.
The following description and the annexed drawings set forth in detail certain illustrative aspects of the subject matter. These aspects are indicative, however, of but a few of the various ways in which the principles of the subject matter may be employed and the present subject matter is intended to include all such aspects and their equivalents. Other objects, advantages and novel features of the subject matter will become apparent from the following detailed description of the subject matter when considered in conjunction with the drawings.
The foregoing and other features and advantages of the present subject matter will become apparent to those skilled in the art to which the present subject matter relates upon reading the following description with reference to the accompanying drawings. It is to be appreciated that two copies of the drawings are provided; one copy with notations therein for reference to the text and a second, clean copy that possibly provides better clarity.
The present subject matter relates generally to devices for the fixation and support of vertebrae. In particular, the present subject matter relates to implant devices having adjustability. The spinal column of vertebrates provides support to bear weight and protection to the delicate spinal cord and spinal nerves. The spinal column includes a series of vertebrae stacked on top of each other. There are typically seven cervical (neck), twelve thoracic (chest), and five lumbar (low back) segments. Each vertebra has a cylindrical shaped vertebral body in the anterior portion of the spine with an arch of bone to the posterior, which covers the neural structures. Between each vertebral body is an intervertebral disk, a cartilaginous cushion to help absorb impact and dampen compressive forces on the spine. To the posterior, the laminar arch covers the neural structures of the spinal cord and nerves for protection. At the junction of the arch and anterior vertebral body are articulations to allow movement of the spine.
Various types of problems can affect the structure and function of the spinal column. These can be based on degenerative conditions of the intervertebral disk or the articulating joints, traumatic disruption of the disk, bone or ligaments supporting the spine, tumor or infection. In addition, congenital or acquired deformities can cause abnormal angulation or slippage of the spine. Anterior slippage (spondylolisthesis) of one vertebral body on another can cause compression of the spinal cord or nerves. Patients who suffer from one of more of these conditions often experience extreme and debilitating pain, and can sustain permanent neurological damage if the conditions are not treated appropriately.
Alternatively or in addition, there are several types of spinal curvature disorders. Examples of such spinal curvature disorders include, but need not be limited to, lordosis, kyphosis and scoliosis.
One technique of treating spinal disorders, in particular the degenerative, traumatic and/or congenital issues, is via surgical arthrodesis of the spine. This can be accomplished by removing the intervertebral disk and replacing it with implant(s) and/or bone and immobilizing the spine to allow the eventual fusion or growth of the bone across the disk space to connect the adjoining vertebral bodies together. The stabilization of the vertebra to allow fusion is often assisted by the surgically implanted device(s) to hold the vertebral bodies in proper alignment and allow the bone to heal, much like placing a cast on a fractured bone. Such techniques have been effectively used to treat the above-described conditions and in most cases are effective at reducing the patient's pain and preventing neurological loss of function.
The spinal curvature disorders and/or contour issues present on the surfaces of the vertebrae may present additional challenges. As such, there is need for further improvement. The present subject matter is such improvement. The present subject matter will now be described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. It is to be appreciated that the various drawings are not necessarily drawn to scale from one figure to another nor inside a given figure, and in particular that the size of the components may be arbitrarily drawn for facilitating the understanding of the drawings. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present subject matter. It may be evident, however, that the present subject matter can be practiced without these specific details. Additionally, other embodiments of the subject matter are possible and the subject matter is capable of being practiced and carried out in ways other than as described. The terminology and phraseology used in describing the subject matter is employed for the purpose of promoting an understanding of the subject matter and should not be taken as limiting.
The implant device and any portions or combination of portions thereof, such as those described and illustrated herein, can be constructed from radiopaque or radiolucent materials, other materials or combinations of such materials. Radiolucent materials can include, but are not limited to, polymers, carbon composites, fiber-reinforced polymers, plastics, combinations thereof and the like. One example of a radiolucent material that can be used with the present subject matter is PEEK-OPTIMA® polymer (commercially available from Invibio Inc., Greenville, S.C., USA). The PEEK-OPTIMA® polymer is a polyaromatic semicrystalline thermoplastic known generically as polyetheretherketone. The PEEK-OPTIMA® polymer is a biocompatible and inert material. Radiopaque materials are traditionally used to construct devices for use in the medical device industry. Radiopaque materials can include, but are not limited to, metal, aluminum, stainless steel, titanium, titanium alloys, cobalt chrome alloys, combinations thereof and the like.
Radiolucent materials can be utilized to facilitate radiographic evaluation of fusion material or vertebrae near an implant device. For example, radiolucent materials permit x-rays to pass through the implant device or components thereof so that developed x-ray pictures provide more visibility of the fusion material and vertebrae without significant interference, such as imaging artifacts, caused by the implant device. Radiolucent materials can enable clear visualization through imaging techniques such as x-ray and computer tomography (CT), whereas traditional radiopaque metallic or alloy materials can generate imaging artifacts or scatter that may prevent a comprehensive inspection of the surrounding tissue, vertebra and fusion material. In order to address the general disadvantage that some radiolucent materials lack the strength of radiopaque materials, design modifications may be required to provide adequate structural integrity and durability to the implant device. For example, the thickness of portions of the implant device subject to stress and strain can be increased in order to add support and structural integrity. Thicker or bulkier construction can mitigate the stresses of vertebral migration, subsidence and/or toggling of the implant components and/or bone fasteners that may cause the implant device to bend, crack or otherwise be damaged while in use.
Referring initially to
The implant device 10 illustrated in
In the disclosed embodiment, each member may include a plurality of engagement areas—such as wherein the engagement areas can be divided as desired into a plurality of areas such as an anterior wall section, a posterior wall section, a medial wall section, a lateral walls section and/or other sections. The areas can be via any divisions. For example, the engagement areas could be four corner areas. As another example, the engagement areas could be four areas defined to be fore, aft, left lateral and right lateral. It is to be appreciated that the choice of division into engagement areas need not be an overall limitation upon the subject matter.
In the disclosed embodiment, each of the members can desirably “nest” or otherwise stack or engage with adjacent members to create a “nested,” nestled or composite layered implant. In the embodiment disclosed in
In the embodiment of
Referring to
The cage bodies 312, 314, 316, 318 each have a graft chamber GC, whose dimensions and position may be varied by varying the thicknesses and/or shapes of the walls of the respective cage body. For instance, by making one of the four walls of the cage body 312 much thicker than the other three walls, the center of the graft chamber GC may be shifted away from the thicker wall. Further, by altering the inner contours of the walls of a cage body, the shape of the graft chamber GC may be selectively determined. The outer contours of the walls of one or more of the cage bodies 312, 314, 316, 318 may be varied to form cage bodies based on the particular anatomy of a patient.
Referring to
In various embodiments, one or more of the cage bodies 315, 317 may be nested in the cage body 318 to modify the dimensions, position and/or shape of the graft chamber GC in the cage body 318. By selecting wall dimensions and shapes of each of the cage bodies 315, 317, and nesting the cage bodies 315, 317 in a predetermined direction, the dimensions, position and/or shape of the graft chamber GC may be selectively determined. The predetermined direction may comprise, for example, the open end of the cage body 315 facing in the same or a different direction than the open end of the cage body 317. As seen in
In various embodiments, the individual members of a composite layered implant may comprise the same material or may comprise differing materials, with each of the members having a variety of shapes and/or purposes. For example, a composite layered implant may comprise an outer member of titanium or other load-bearing material, with one or more inner members comprising an osteo-inductive and/or osteo-conductive material such as Silicon Nitride. If desired, an intermediate layer of a composite layered implant may comprise a non-loading bearing material such as morselized bone graft and/or granular or powdered silicone nitride, with load bearing members such as titanium or PEEK positioned inside and/or outside of the non-load bearing members. The disclosed modular implants and/or “cage” structures can also allow for various combinations of materials to be integrated and implanted in a single cage. For example, an outer layer if silicon nitride to promote bony ingrowth may “cover” an inner layer of titanium that provides strength and/or support for the implant. In various embodiments, a composite implant incorporating 4 layered members may include 4 differing materials in the implant walls, with an optional amount of bone graft and/or other material located within the central opening or bore of the implant. A variety of such component materials could be employed, including metal, plastics and/or ceramics, including (but not limited to) PEEK, titanium, chrome cobalt, allograft, autograft or xenograft bone or other materials, solid Silicon Nitride (see
In various embodiments, a composite layered implant such as described herein may comprise a plurality of modular members or layers, with multiple nested layers being added and/or removed from the implant to accommodate an individual patient's anatomy and/or the desires of the surgeon. In many cases, a composite layered implant may be assembled at a back-table location during a surgical procedure to desirably achieve a largest and/or optimal footprint for placement between two adjacent vertebrae. By removing and/or adding various layers to the device, a composite layered implant can be created and/or assembled to achieve a desired clinical effect.
For instance, the interbody system 500 may be assembled by attaching the interbody device 510 to the cage 520. In this regard, the interbody device 510 may be positioned so that channels or other guiding features may be aligned with corresponding plate guides on the cage, or other known engagement features, if desired. Once assembled, the interbody system may be implanted between the vertebral bodies and secured to one or more of the vertebral bodies using fixation devices such as bone screws (not shown).
The cage bodies 224A, 224B, 224C may have any shape that may be implemented in an application between vertebral bodies, as will be understood by those skilled in the art. For instance, the cage bodies 224A, 224B, 224C may have a trapezoidal shape, with the side walls tapered inward in the posterior direction (not shown), or the shape of the cage bodies 224A, 224B, 224C may be a square, rectangular, elliptical, circular, semicircular, or the like. The end caps 221A, 221B, 225 may have a shape that matches the shape of the cage bodies 224A, 224B, 224C.
As seen in
Similarly, the thickness, size and/or shape of the rim portion 222A may be varied to, for example, match anatomical requirements for particular applications of the cage system. For instance, the height of the walls that form the rim portion 222A may be decreased (or increased) in the posterior (or anterior) direction, so as to provide better fit in vertebral interbody applications. The rim portion 222A may be configured to contact and engage a vertebral body. In this regard, the surface of the rim portion 222A may be contoured to match the shape of the vertebral body. The surface may include bone interface members that may be configured to aggressively grip against the bony surface of the adjacent vertebral body.
As best seen in
In various embodiments, a modular implant system could include upper and/or lower endcaps that could integrate with various system components, including a modular composite cage, to alter the size, shape, footprint and/or tilt of the implant. The endcaps could individually fit in one side and/or end of the cage, and/or into both sides and/or ends of the cage, and the system could include a variety of locking features for securing the endcap(s) to each other and/or to the cage (and/or could secure the entire modular implant together, if desired).
Note that, in various alternative embodiments, variations in the position and/or relationships between the various figures and/or modular components are contemplated, such that different relative positions of the various modules and/or component parts, depending upon specific module design and/or interchangeability, may be possible. In other words, different relative adjustment positions of the various components may be accomplished via adjustment in separation and/or surface angulation of one of more of the components to achieve a variety of resulting implant shapes and/or sizes, thereby accommodating virtually any expected anatomical variation. For example, variation of the thicknesses and/or separation distance between the end caps (i.e., optionally without altering the angulation of the end cap surfaces) can desirably cause an increase or decrease in the size or “height” of the implant, due to changes in the z-axis positioning of the implant components which engage the adjacent vertebrae. Concurrently, alterations in the “tilt angle” or angulation of one or both of the surfaces of the end caps or other components in the medial-lateral (i.e., rotation about a y-axis) and/or anterior-posterior (i.e., rotation about an x-axis) axes of the implant will allow the implant to accommodate a wide variety of natural and/or surgically altered surfaces of the spine. Moreover, various complex combinations (at various amounts) of comparative lateral (e.g., left-right) tilt and fore-aft (e.g., anterior-posterior) tilt can be accomplished, with or without concurrent adjustments in the height of the implant. In various embodiments, each respective surface of a composite implant, and end cap or other components (e.g., each corner) of a given component can have a different adjusted distance as compared to the other respective engagement areas (e.g., other corners), if desired.
The various embodiments of a composite modular implant device disclosed herein can be configured to interact with two bone vertebrae of a spine. The spine may have any of several types of spinal curvature disorders which are sought to be treated. Examples of such spinal curvature disorders include, but need not be limited to, lordosis, kyphosis, scoliosis and/or low and/or high velocity fractures, among other pathologies.
In various exemplary scenarios, the implant devices disclosed herein can be utilized to fix and/or secure adjacent vertebrae that have had cartilaginous disc between the vertebrae replaced with fusion material that promotes the fusion of the vertebrae, such as a graft of bone tissue. Also, such can be accomplished even when dealing with a spinal curvature disorder (e.g., lordosis, kyphosis and scoliosis).
Of course, method(s) for manufacturing the implant device and implanting the device into a spine are contemplated and are part of the scope of the present application.
While embodiments and applications of the present subject matter have been shown and described, it would be apparent to those skilled in the art that many more modifications are possible without departing from the inventive concepts herein. The subject matter, therefore, is not to be restricted except in the spirit of the appended claims.
All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.
The various headings and titles used herein are for the convenience of the reader, and should not be construed to limit or constrain any of the features or disclosures thereunder to a specific embodiment or embodiments. It should be understood that various exemplary embodiments could incorporate numerous combinations of the various advantages and/or features described, all manner of combinations of which are contemplated and expressly incorporated hereunder.
The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., i.e., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.
Preferred embodiments of this invention are described herein, including the best mode known to the inventor for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventor expects skilled artisans to employ such variations as appropriate, and the inventor intends for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.
Claims
1. A modular implant device for the spine, the modular implant device for location between two adjacent vertebrae, comprising:
- a first member sized to span a distance between the two adjacent vertebrae, the first member including a first upper engagement surface for engaging a first lower endplate portion of a first vertebral body of the two adjacent vertebrae and a first lower engagement surface for engaging a first upper endplate portion of a second vertebral body of the two adjacent vertebra, the first member formed from a first material;
- a second member sized to span the distance between the two adjacent vertebrae, the second member including a second upper engagement surface for engaging a lower endplate of a first vertebral body of the two adjacent vertebrae and a second lower engagement surface for engaging an upper endplate of a second vertebral body of the two adjacent vertebrae, the second member formed from a second material, the first material being different from the second material; and
- the first member further comprising a first opening extending from the first upper engagement surface to the first lower engagement surface;
- wherein the second member is sized and configured to fit inside of the first opening.
2. The modular implant device of claim 1, wherein a first distance between the first upper engagement surface and the first lower engagement surface equals a second distance between the second upper engagement surface and the second lower engagement surface.
3. The modular implant device of claim 1, wherein when the second member is inside of the first opening, the first and second upper engagement surfaces are coplaner.
4. The modular implant device of claim 1, wherein when the second member is inside of the first opening, the first and second lower engagement surfaces are coplaner.
5. The modular implant device of claim 3, wherein when the second member is inside of the first opening, the first and second upper engagement surfaces are coplaner.
6. The modular implant device of claim 1, wherein the first member comprises titanium and the second member comprises silicon nitride.
7. The modular implant device of claim 1, wherein the second member comprises titanium and the first member comprises silicon nitride.
8. The modular implant device of claim 1, further comprising:
- a third member sized to span the distance between the two adjacent vertebrae, the third member including a third upper engagement surface for engaging a lower endplate of the first vertebral body of the two adjacent vertebrae and a third lower engagement surface for engaging an upper endplate of the second vertebral body of the two adjacent vertebrae; and
- the second member further comprising a second opening extending from the first upper engagement surface to the first lower engagement surface;
- wherein the third member is sized and configured to fit inside of the second opening.
9. The modular implant device of claim 8, wherein the first, second and third members each comprise a locking opening, and the first, second and third members are secured together by a locking pin extending through the locking openings in the first, second and third members.